Shear valves can be utilized in fluid dispensing systems, such as gasoline refueling stations and the like. For example, in some cases a vehicle or other component can collide with a fuel dispenser, causing the dispenser to be displaced from its fluid supply line. Shear valve assemblies are designed to provide a breakaway point at which the fluid supply system can break, shear or separate, while also provide a closing valve or valves to prevent or minimize loss of fuel. However, many shear assemblies do not perform satisfactorily, particularly when used with pressurized fluid.